The invention is based on a wiper blade for cleaning motor vehicle windows.
Known windshield or window wipers have a wiper arm, which is constructed of a fastening part, secured to a drive shaft, a link part joined to it via a toggle joint, and a wiper rod rigidly adjoining the link part. The windshield wiper also has a wiper blade, which has a support bracket system and a wiper strip retained by the support bracket system. The wiper blade is pivotably connected to the wiper arm by the provision that a hooklike end of the wiper rod engages between two side cheeks of the support bracket system and includes a link bolt. The joint thus formed guides the wiper blade with the wiper strip over a motor vehicle window; the link part and the support bracket system make it possible for the wiper strip to adapt to a curvature of the motor vehicle window. A requisite contact pressure of the wiper strip on the motor vehicle window is attained with at least one tension spring, which tenses the fastening part and the link part jointly with the wiper rod, via the toggle joint.
The wiper strip comprises an elastomer. It has a head strip, which is joined via a tilted rib to a wiper lip that rests on the window to be wiped. By means of the tilting rib, at the turning point of the wiper motion the wiper strip can flip over in the opposite direction, so that it always assumes a favorable angle to the windshield. If the windshield wiper is actuated, the wiper strip slides with the wiper lip over the motor vehicle window. When the motor vehicle is in motion, a relative wind flows under the wiper arm and the wiper blade and generates a force counter to the contact pressure of the tension spring. Especially at high speeds, the relative wind can reduce the contact pressure of the wiper blade on the windshield so much that the wiper blade will lift from the windshield and float on a film of water, or that the wiper lip of the wiper strip will be blown over. This causes jittering of the wiper blade on the windshield and makes the cleaning quality inadequate.
It is known to secure a wind deflector in the downward wiping direction in front of the wiper blade on the driver""s side; this wind deflector conducts the relative wind over the wiper blade and thus presses the wiper blade against the vehicle window. To prevent the relative wind from flowing under the wind deflector and causing wind noises and reducing the contact pressure, the wind deflector should be disposed with a lower edge as close as possible to the windshield. The closer the spacing between the wind deflector and the windshield, the better the relative wind is carried over the wiper blade, but also the sooner the wind deflector comes into contact with the windshield, for instance at various influential variables that occur together, such as play between individual components, deformation of individual components because of a strong relative wind, and so forth.
From German Patent DE 195 28 015 C1, a wiper blade with a wind deflector is known on which an elastic wind conducting element is secured; this element is disposed approximately parallel to the wiper lip, near the windshield, and is elastically braced or is elastically deformable in such a way that at higher vehicle speeds, and at the relative wind, it presses against on the windshield, at least in a wiping region.
Water, such as rainwater or cleaning fluid from the windshield washer nozzles, and so forth that strikes the support bracket system and/or the wind deflector and adheres to it is often blown by the relative wind during wiping onto an area of the windshield that is already been wiped and thus hinders the view.
According to the invention, at least one gutter oriented in the longitudinal direction is disposed directly or indirectly on a support bracket system and conducts water outward of a main viewing field. Water striking the wiper blade and already adhering to it is blown by the relative wind into the gutter and inside it is blown outward in the longitudinal direction out of the viewing field, specifically toward the end that points upward during wiping. The water is carried outward in a purposeful way, and areas of the windshield that have already been wiped remain free of water adhering to the wiper blade, and the view is improved.
Wind deflectors have a large closed surface area, which compared to a support bracket system is struck by larger quantities of water. In addition, in both the downward wiping motion and the upward wiping motion, the wind deflector conducts the relative wind over the support bracket system. Particularly in the downward wiping motion, water from the wind deflector is blown onto the cleaned windshield. It is therefore especially advantageous that at least one gutter is disposed on the wind deflector. Water primarily strikes a front side facing into the relative wind. The relative wind blows the water more or less, depending on the position of the wiper, into an upper region of the wind deflector that is remote from the window. In one feature of the invention, the gutter is disposed in the upper region of the wind deflector, as much as possible on its uppermost edge, or else the gutter forms the uppermost edge of the wind deflector. The less area there is remaining toward the top downstream of the gutter, the more completely can the water be conducted on the wind deflector into the gutter and outward, and that much less water is blown from a still remaining area above the gutter onto the already-cleaned windshield.
Sometimes water can reach an inside of the wind deflector facing away from the relative wind, primarily via a lower edge, facing toward the windshield, for instance from a stream of water from a windshield washer during wiping. To prevent this water from passing from the inside into the main viewing field of the windshield, it is proposed that at least one gutter be disposed on the inside of the wind deflector. In the lower region of the wind deflector and/or in the upper region of the wind deflector, the water can be caught with a gutter and conducted to the outside.
In one feature, the gutter is disposed on an upper edge of the wind deflector, on the side facing away from the window, and protrudes in the direction of the support bracket system past the inside of the wind deflector and in the direction away from the support bracket system it protrudes past the front side of the wind deflector. With a gutter, water can advantageously be caught from the front side and from the inside and conducted outward. This dispenses with a second, additional component for a gutter on the inside.
The gutter can be secured to the support bracket system or to the wind deflector by nonpositive, positive and/or material engagement, for instance via a plug-type, clamping, adhesive, and/or welded connection. Especially advantageously, however, the gutter is embodied integrally with the support bracket system and/or with the wind deflector. This dispenses with additional components, assembly steps, and expense. The gutter can be formed by a protrusion that protrudes past the surface of the wind deflector, or by an indentation made in the surface. With an indentation, there is economy of both material and weight. Moreover, the wind deflector can be embodied in a streamlined fashioned, with only slight turbulence at the gutter.
In a further feature, it is proposed that instead of one gutter, a plurality of gutters be made in the surface of the front side of the wind deflector by indentations. Each of the gutters then has to carry less water outward and as a result can be especially small and streamlined in form. The gutters can be formed onto the wind deflector during casting or can be made later, for instance by metal-cutting machining, or with a heat source or ultrasound source, and so forth.
To prevent water from being blown out of the gutter by the relative wind, the gutter is closed in the direction facing away from or in the direction of the window.